15 



Sculptures bestaar af meget fine Spirallinier og talrige, 

 lidet bøiede, svage axiale Ribber, der ofte gaar over til 

 fine Linier eller Vækststriber hvorved dannes et lint 

 Netværk. 



Apex : Fig. 22 a, stump og glat. Første Vinding har 

 omtrent samme Sculptur som de øvrige. 



Operculum ovalt. 



Tændeme, Tab. X. Fig. 19, ligne Bela Trevelyana. 



Forekomst: St. 35, 40, 240, 295, 283, 312 og 353 

 fra 658 til L333 Favne. 



Dr. Jeffreys sendte mig med sin sædvanlige Imøde- 

 kommenhed Fleurotoma exigua fra „Triton" Exped. til 

 Sammenligning, men naar undtages, at den axiale Sculptur 

 lios denne var unget kraftigere end paa mine Exemplarer fra 

 de større Dyl> i Nordhavet, fandt jeg ingen nævneværdig 

 Afvigelse, og jeg kan derfor ikke betragte dem som arts- 

 afvigende. Jeg skylder dog at tilføie, at min afdøde Ven 

 var ikke enig med mig i denne Opfatning. Prof. Verrill har 

 ligeledes været saa venlig at sende mig tiere Exemplarer af 

 Bela pygmæa. Disse stemme fuldstændig med vor Art. 

 Verrill angiver Dybdeforholdene for B. pygmæa i „2d 

 Catalog" 1883 fra 312 til 1290 Favne. 



Bela bicarinata, Couth. 



Pl. VIII, Fig. 18, 19, Pl. X. Fig. i:., ir,. 



Pleurotoma bicarinata, Couthouy, Boston Journ. Nat. Hist. 



II 18311. Pag. 104, Pl. 1, Fig. 11. 

 Fleurotoma violacea, Migh. Proc. Boston Soc. Nat. Hist. I 



1841, Pag. 50. 

 Defrancia cylindracea, livida & Beckii, Møller, Krøyers 



. Tidsskr. 1842, Pag. 86 & 87. 

 Bela bicarinata & violacea, (4. O. Sårs. Moll. reg. are. 



Pag. 237, Tab. lb\ Fig. 11. 12 Oe Tab. 17. Fig. 2. 3. 

 „ bicarinata, Verrill, Cat. mar. Moll. 1882. Pag. 482, 



Pl. LVII, Fig. li', 



At karakterisere denne Art er hoist vanskeligt. thi 

 baade Form og Sculptur er mer,' vexlende end i nogen 

 anden af hele Shegten. Snart er Formen 'nal med Spiret 

 omtrent af samme Længde som Mundaabningen, snart fusi- 

 form med et hengere stærkt tilspidset Spir; Vindingerne 

 er snart kjølede, snart afrundede cylindriske; Sculpturen 

 er snart overveiende kraftigst i den axiale Retning, snart 

 i den transversale. Den typiske bicarinata hai' saaledes 

 meget stærke Spiralribber uden anden axial Sculptur end 

 Væxtstriber, hvorimod Varieteterne violacea og ci/liailra<ea 

 olle hai' ganske kraftige axiale Ribber og disse er altid. 

 selv om de kun optræder som Væxtstriber, hoiede. Mest 



open. The sculpture consists of wry line spiral striations 

 and numerous, hut slightly curved, faint, axial ribs which, 

 frequently, pass into line striations. or lines of growth and. 

 thus, form a delicate reticulation. 



Apex (tig. 22 a) blunl and smooth. The first whorl 

 has a sculpture much similar to the others. 



Operculum oval. 



The teeth (PI. X. tig. 19) resemble those of Bela 

 Tvevelyana. 



Habitat: Stats. Nos. 35, 4». 24), 283, 2 l Jf>, 312, 

 353, in from 658 to 1333 fathoms. 



Dr. Jeffreys with his usual amiability sent me. for 

 comparison. Pleurotoma exigua from the ..Triton- Expedi- 

 tion, hut. with exec], tinn that the axial sculpture was 

 somewhat stronger than in my specimens from the vast 

 depths of the North Atlantic ocean, I found no variation 

 worthy of notice, between it and />'. oralis, and I cannot, 

 therefore, consider them as distinguishable species. I ought, 

 however, to add that my friend did not concur in this 

 conclusion with me. Prof. Verrill has, also, been so kind 

 as to send me several specimens ,,f Bela pygmæa. Tics,. 

 accord, completely, with our species. Verrill gives the 

 Soundings for /;. pygmæa in -'2nd Catalogue- 1884, as. 

 from 312 to 1290 fathoms. 



Bela bicarinata, Couth. 



PI. VIII, figs. 18, in, PI. X, figs. 15, 16. 



Pleurotoma bicarinata, Couthouy. Boston Journal Nat. 



Hist. II 1839, pag. 105, PI. I, tig. 11. 

 Pleurotoma violacea, Migh. Proc. Boston Soc. Nat. Hist. 



I 1841. pag. fill. 

 Defrancia n/liuihwea, livida cO Beckii, Moller, Krøyer's 



Tidskr. 1842, Pl. 86, 87. 

 Bela bicarinata & violacea, Gr. O. Sårs, Moll. reg. are. 



pag. 237, Pl. XVI. tig. 1 f. 12 and Pl. XVII, tigs. 2. 3. 

 ., bicarinata, Verrill, Cat, mar. Moll. 18s2, pag. 482, 



Pl. LVII, fig. 16. 



It is extremely difficult to characterise this species, 

 because both its form and sculpture are more variable than 

 in any other of the whole genus. Sometimes the form is 

 oval, with the spire about the same length as the aperture, 

 and sometimes it is fusiform, with a. long, strongly acu- 

 minate spire. The whorls are sometimes angulated and 

 sometimes cylindrical^ rounded. The sculpture is, often, 

 by far the most prominent in the axial direction, and 

 often, it is so transversally. The typical bicarinata 

 has. thus, very prominent spiral ribs devoid of other sculp- 

 ture than lines of growth, whilst the varieties violacea and 

 cylindracea, frequently, have quite prominent axial ribs, and 



